Criminal - Jury - Vetrovec Caution. R. v. Cargioli
In R. v. Cargioli (Ont CA, 2023) the Court of Appeal considered appeals by three defendants from convictions, one for first-degree murder and two for second-degree murder. In this extract the court considers the deference to be accorded the trial judge in deciding when to issue a Vetrovec instruction to the jury:
 Ultimately, it was for the trial judge in the exercise of his discretion to decide whether a Vetrovec instruction was necessary: R. v. Boone, 2016 ONCA 227, 28 C.R. (7th) 1, at paras. 50-51, leave to appeal refused,  S.C.C.A. No. 238. The trial judge’s decision that a Vetrovec instruction would be inappropriate based upon a single feature of Ms. Taleb’s evidence falls within the scope of that discretion.. R. v. I.M.
In R. v. I.M. (Ont CA, 2023) the Court of Appeal commented on Vetrovec cautions, which are trustworthiness warnings that a trial judge can give regarding the evidence of co-defendants:
 The appellant argues that the trial judge should have provided a Vetrovec warning concerning the evidence of G.D., emphasizing that his was the only evidence that the appellant was in the alleyway. According to the appellant, although G.D. was not a classic Vetrovec witness, such as an accomplice or a jailhouse informant, his evidence was essential to the Crown’s case and he had a motive to lie and credibility problems. These factors, in combination, were sufficient to require a Vetrovec warning in the circumstances of this case. G.D. had a motive to lie because S.T. was within his circle of friends – S.T. was G.D.’s friend’s sister’s boyfriend, and a friend of G.D.’s friend Daniel. Moreover, G.D. believed he might be paid by the police. His credibility problems included a youth record for possessing a prohibited firearm. According to the appellant, G.D.’s evidence was riddled with inconsistencies and implausibility.. R. v. Mohamed
 We do not agree that a Vetrovec warning concerning G.D.’s evidence was mandatory in the circumstances of this case, and we are satisfied that the trial judge’s jury instructions were sufficient to equip the jury to properly assess his evidence.
 In general, the decision whether to provide a Vetrovec warning is a discretionary one: R. v. Ranglin, 2018 ONCA 1050, 370 C.C.C. (3d) 477, at paras. 32-34. Trial counsel did not take the position that a Vetrovec warning was required. This is not determinative, but it provides strong support for the trial judge’s view that a Vetrovec warning was not required. The trial judge specifically asked the appellant whether he wanted a Vetrovec warning in respect of two other witnesses. He did not.
In R. v. Mohamed (Ont CA, 2023) the Court of Appeal considered the nature of a Vetrovec witness and the caution that must be exercised with a jury:
(1) A.A. was a Vetrovec Witness
 Where there are objective reasons to suspect the credibility of the testimony of a Crown witness, the witness is a Vetrovec witness, and the trial judge must, within the bounds of reasonable discretion, warn a jury to view their evidence with caution: R. v. Carroll, 2014 ONCA 2, 304 C.C.C. (3d) 252; R. v. Deol, 2017 ONCA 221, 352 C.C.C. (3d) 343. In R. v. Bradshaw, 2017 SCC 35,  1 S.C.R. 865, at para. 69, Karakatsanis J. noted, for the majority, that, “[g]iven that a Vetrovec witness cannot be trusted to tell the truth, even under oath …, establishing that hearsay evidence from a Vetrovec witness is inherently trustworthy will be extremely challenging” (citations omitted).